How fast and far does the solar wind blow?

450 kilometers/sec near the Earth, but there are low-speed and high-speed streams within this wind that travel 200 to 1000 km/sec. The wind blows with essentially the same speed all the way out to the orbit of Neptune, and it is expected that by a distance of 150 Astronomical units it impacts the interstellar medium and forms a shock front where it suddenly decelerates. This is called the heliopause, and the Voyager and Pioneer spacecraft are expected to reach it in the early part of the next century.

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All answers are provided by Dr. Sten Odenwald (Raytheon STX) for the
NASA IMAGE/POETRY Education and Public Outreach program.